This film concerns a writer of mystery stories who bases his villain on a criminal, played by Malcolm McDowell, who is incarcerated in prison. Escaping prison after his apparent death in a fire, the criminal plans to revenge himself on the writer (Roger Moore) for 'stealing his personality', and proceeds to carry out a set of murders based around the novels. Moore is unable to convince the authorities of the true murderer and, alerted by an avid fan (Nancy Allen) who has psychic powers, seeks to trap McDowell into giving himself away.